/* -*- Mode: C; tab-width: 4 -*-
*
* Copyright (c) 2002-2003 Apple Computer, Inc. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <stdio.h> // For printf()
#include <string.h> // For strcpy()
#include <Events.h> // For WaitNextEvent()
#include <CodeFragments.h> // For SIOkUnresolvedCFragSymbolAddress
#include <SIOUX.h> // For SIOUXHandleOneEvent()
#include <OpenTransport.h>
#include <OpenTptInternet.h>
#include "dns_sd.h"
#define ns_c_in 1
#define ns_t_a 1
typedef union { UInt8 b[2]; UInt16 NotAnInteger; } mDNSOpaque16;
static UInt16 mDNSVal16(mDNSOpaque16 x) { return((UInt16)(x.b[0]<<8 | x.b[1])); }
static mDNSOpaque16 mDNSOpaque16fromIntVal(UInt16 v)
{ mDNSOpaque16 x; x.b[0] = (UInt8)(v >> 8); x.b[1] = (UInt8)(v & 0xFF); return(x); }
typedef struct
{
OTLIFO serviceinfolist;
Boolean headerPrinted;
Boolean lostRecords;
} SearcherServices;
typedef struct
{
SearcherServices *services;
char name[kDNSServiceMaxDomainName];
char type[kDNSServiceMaxDomainName];
char domn[kDNSServiceMaxDomainName];
char host[kDNSServiceMaxDomainName];
char text[kDNSServiceMaxDomainName];
InetHost address;
mDNSOpaque16 notAnIntPort;
DNSServiceRef sdRef;
Boolean add;
Boolean dom;
OTLink link;
} linkedServiceInfo;
static SearcherServices services;
// PrintServiceInfo prints the service information to standard out
// A real application might want to do something else with the information
static void PrintServiceInfo(SearcherServices *services)
{
OTLink *link = OTReverseList(OTLIFOStealList(&services->serviceinfolist));
while (link)
{
linkedServiceInfo *s = OTGetLinkObject(link, linkedServiceInfo, link);
if (!services->headerPrinted)
{
printf("%-55s Type Domain Target Host IP Address Port Info\n", "Name");
services->headerPrinted = true;
}
if (s->dom)
{
if (s->add) printf("%-55s available for browsing\n", s->domn);
else printf("%-55s no longer available for browsing\n", s->domn);
}
else
{
char ip[16];
unsigned char *p = (unsigned char *)&s->address;
sprintf(ip, "%d.%d.%d.%d", p[0], p[1], p[2], p[3]);
printf("%-55s %-16s %-14s ", s->name, s->type, s->domn);
if (s->add) printf("%-15s %-15s %5d %s\n", s->host, ip, mDNSVal16(s->notAnIntPort), s->text);
else printf("Removed\n");
}
link = link->fNext;
OTFreeMem(s);
}
}
static void FoundInstanceAddress(DNSServiceRef sdRef, DNSServiceFlags flags, uint32_t interfaceIndex, DNSServiceErrorType errorCode,
const char *fullname, uint16_t rrtype, uint16_t rrclass, uint16_t rdlen, const void *rdata, uint32_t ttl, void *context)
{
linkedServiceInfo *info = (linkedServiceInfo *)context;
SearcherServices *services = info->services;
(void)sdRef; // Unused
(void)interfaceIndex; // Unused
(void)fullname; // Unused
(void)ttl; // Unused
if (errorCode == kDNSServiceErr_NoError)
if (flags & kDNSServiceFlagsAdd)
if (rrclass == ns_c_in && rrtype == ns_t_a && rdlen == sizeof(info->address))
{
memcpy(&info->address, rdata, sizeof(info->address));
DNSServiceRefDeallocate(info->sdRef);
OTLIFOEnqueue(&services->serviceinfolist, &info->link);
}
}
static void FoundInstanceInfo(DNSServiceRef sdRef, DNSServiceFlags flags, uint32_t interfaceIndex,
DNSServiceErrorType errorCode, const char *fullname, const char *hosttarget, uint16_t notAnIntPort,
uint16_t txtLen, const unsigned char *txtRecord, void *context)
{
linkedServiceInfo *info = (linkedServiceInfo *)context;
SearcherServices *services = info->services;
(void)sdRef; // Unused
(void)flags; // Unused
(void)interfaceIndex; // Unused
(void)errorCode; // Unused
(void)fullname; // Unused
strcpy(info->host, hosttarget);
if (txtLen == 0) info->text[0] = 0;
else
{
strncpy(info->text, (char *)txtRecord+1, txtRecord[0]);
info->text[txtRecord[0]] = 0;
}
info->notAnIntPort.NotAnInteger = notAnIntPort;
DNSServiceRefDeallocate(info->sdRef);
DNSServiceQueryRecord(&info->sdRef, 0, 0, info->host, ns_t_a, ns_c_in, FoundInstanceAddress, info);
}
// When a new named instance of a service is found, FoundInstance() is called.
// In this sample code we turn around and immediately to a DNSServiceResolve() to resolve that service name
// to find its target host, port, and txtinfo, but a normal browing application would just display the name.
// Resolving every single thing you find can be quite hard on the network, so you shouldn't do this
// in a real application. Defer resolving until the client has picked which instance from the
// long list of services is the one they want to use, and then resolve only that one.
static void FoundInstance(DNSServiceRef client, DNSServiceFlags flags, uint32_t interface, DNSServiceErrorType errorCode,
const char *replyName, const char *replyType, const char *replyDomain, void *context)
{
#pragma unused(client, interface, errorCode)
SearcherServices *services = (SearcherServices *)context;
linkedServiceInfo *info;
if (!services) { DebugStr("\pFoundInstance: services is NULL"); return; }
info = (linkedServiceInfo *)OTAllocMem(sizeof(linkedServiceInfo));
if (!info) { services->lostRecords = true; return; }
info->services = services;
strcpy(info->name, replyName);
strcpy(info->type, replyType);
strcpy(info->domn, replyDomain);
info->text[0] = 0;
info->add = (flags & kDNSServiceFlagsAdd) ? true : false;
info->dom = false;
if (!info->add) // If TTL == 0 we're deleting a service,
OTLIFOEnqueue(&services->serviceinfolist, &info->link);
else // else we're adding a new service
DNSServiceResolve(&info->sdRef, 0, 0, info->name, info->type, info->domn, FoundInstanceInfo, info);
}
// YieldSomeTime() just cooperatively yields some time to other processes running on classic Mac OS
static Boolean YieldSomeTime(UInt32 milliseconds)
{
extern Boolean SIOUXQuitting;
EventRecord e;
WaitNextEvent(everyEvent, &e, milliseconds / 17, NULL);
SIOUXHandleOneEvent(&e);
return(SIOUXQuitting);
}
int main()
{
OSStatus err;
void *tempmem;
DNSServiceRef sdRef;
DNSServiceErrorType dse;
SIOUXSettings.asktosaveonclose = false;
SIOUXSettings.userwindowtitle = "\pMulticast DNS Searcher";
SIOUXSettings.rows = 40;
SIOUXSettings.columns = 160;
printf("DNS-SD Search Client\n\n");
printf("This software reports errors using MacsBug breaks,\n");
printf("so if you don't have MacsBug installed your Mac may crash.\n\n");
printf("******************************************************************************\n\n");
if (DNSServiceBrowse == (void*)kUnresolvedCFragSymbolAddress)
{
printf("Before you can use mDNS/DNS-SD clients, you need to place the \n");
printf("\"Multicast DNS & DNS-SD\" Extension in the Extensions Folder and restart\n");
return(-1);
}
err = InitOpenTransport();
if (err) { printf("InitOpenTransport failed %d", err); return(err); }
// Make sure OT has a large enough memory pool for us to draw from at OTNotifier (interrupt) time
tempmem = OTAllocMem(0x10000);
if (tempmem) OTFreeMem(tempmem);
else printf("**** Warning: OTAllocMem couldn't pre-allocate 64K for us.\n");
services.serviceinfolist.fHead = NULL;
services.headerPrinted = false;
services.lostRecords = false;
printf("Sending mDNS service lookup queries and waiting for responses...\n\n");
dse = DNSServiceBrowse(&sdRef, 0, 0, "_http._tcp", "", FoundInstance, &services);
if (dse == kDNSServiceErr_NoError)
{
while (!YieldSomeTime(35))
{
if (services.serviceinfolist.fHead)
PrintServiceInfo(&services);
if (services.lostRecords)
{
services.lostRecords = false;
printf("**** Warning: Out of memory: Records have been missed.\n");
}
}
}
DNSServiceRefDeallocate(sdRef);
CloseOpenTransport();
return(0);
}
